1. Field of the Invention
The present invention relates to a pointing device, and more particularly, to a pointing apparatus using a piezoelectric film, a method for producing the apparatus, and apparatus and method for detecting pointing information therefor. The present application is based on Korean Application No. 2001-60238, which is incorporated herein by reference.
2. Description of the Related Art
A conventional apparatus for detecting pointing information can input pointing information from the outside by using a special tool such as a ball or pen. When a disposable ball or pen is lost or worn out, the conventional apparatus for detecting pointing information cannot input pointing information and therefore a ball or pen should be kept for inputting pointing information.
Since the conventional apparatus for detecting pointing information, for example, a mouse, is comprised of elements having a certain size, the mouse cannot be folded or unfolded, and thereby there are limitations in using the mouse.
To solve the above problems, it is a first objective of the present invention to provide a pointing apparatus using a piezoelectric film, which is convenient to carry, is capable of inputting pointing information without a special tool, and can be manufactured with low costs.
It is a second objective to provide a method for producing the pointing apparatus using a piezoelectric film.
It is a third objective to provide an apparatus for detecting pointing information, that is, a moving direction and the amount of movement, by using touch signals, which are generated by the pointing apparatus using a piezoelectric film.
It is a fourth objective to provide a method for detecting pointing information, that is, a moving direction and the amount of movement, by using touch signals, which are generated by the pointing apparatus using a piezoelectric film.
Accordingly, to achieve the first objective, there is provided a pointing apparatus using a piezoelectric film. The apparatus includes a plurality of first strips arranged in a first direction at a first predetermined interval, each of which is extended in a second direction perpendicular to the first direction and is touched when a pointer is moved in the first direction, and a plurality of second strips, which are lapped over the plurality of the first strips and arranged in the second direction at a second predetermined interval, each of which is extended in the first direction and is touched when the pointer is moved in the second direction. Each of the first and second strips generates electric charges in a quantity corresponding to pressure applied by a user and outputs touch signals having levels corresponding to the quantity of the electric charges, and moving direction and amount of movement of the pointer are determined by the number of times and the order in which the touch signals are generated.
To achieve the second objective, there is provided a method for producing the pointing apparatus using a piezoelectric film. The method includes the steps of forming the part of the first strips in a first layer, forming the remainder of the first strips in a second layer, forming part of the second strips in a third layer, and forming the remainder of the second strips in a fourth layer, interlacing the second layer with the first layer to form the first strips in a common layer, and interlacing the fourth layer with the third layer to form the second strips in another common layer, lapping the common layer having the first strips over another common layer having the second strips so that the first strips perpendicularly intersect the second strips, and housing the lapped-over layers.
It is preferable that a method for producing the pointing apparatus using a piezoelectric film includes the steps of forming all the first strips in a fifth layer and forming all the second strips in a sixth layer, lapping the fifth layer over the sixth layer so that the first strips perpendicularly intersect the second strips, and housing the lapped-over layers.
To achieve the third objective, there is provided an apparatus for detecting pointing information. The apparatus includes a signal converting portion for converting the touch signals generated from the first strips into square waves, outputting the square waves as first information signals, converting the touch signals generated from the second strips into square waves, and outputting the square waves as second information signals, a first direction detecting portion for checking the order in which the first information signals are generated, and detecting a component of the first direction of the moving direction from the checked order, and a second direction detecting portion for checking the order in which the second information signals are generated, and detecting a component of the second direction of the moving direction from the checked order. The moving direction corresponds to the pointing information.
It is preferable that the apparatus further includes a first movement amount detecting portion for measuring the number of times in which the first information signals are generated in each predetermined time period, and outputting the number of times as the amount of movement of the first direction, and a second movement amount detecting portion for measuring the number of times in which the second information signals are generated in each predetermined time period, and outputting the number of times as the amount of movement of the second direction. The amount of movement corresponds to the pointing information.
To achieve the fourth objective, there is provided a method for detecting pointing information. The method includes the steps of (a) converting the touch signals generated from the first strips into square waves to obtain the first information signals and converting the touch signals generated form the second strips into the square waves to obtain the second information signals, and (b) checking the order in which the first and second information signals are generated and detecting the components of the first and second directions from the checked order.
It is preferable that in step (b), the numbers of times in which the first and second information signals are generated in each predetermined time period are measured, and the numbers of times are determined as the amounts of movement of the first and second directions, respectively.